Canada’s Marsh Brothers Aviation has incorporated its proprietary thermoplastic polymer bearing AeroTough® GF (grease-free) technology into a new flap roller upgrade kit for the Beechcraft King Air light aircraft range.

The King Air Flap Roller Upgrade Kit has been developed to replace the traditional greased flap rollers supplied by the original equipment manufacturer (OEM) with an alternative self-lubricating, lightweight polymer material to prevent seizure and reduce metal-to-metal contact.

Nicholas Choo-Son, Director, New Business Development at Marsh Brothers Aviation, explained the advantages of the upgrade for King Air operators.  

“The problem with the OEM flap roller is two-fold,” he said. “First, they are a traditional sealed grease-packed needle roller bearing that relies on supplemental grease for lubrication. Once the grease begins to dry and degrade, the performance of the roller begins to deteriorate. Secondly, installation is relatively complicated involving the rollers, either a metal or a phenolic washer and Teflon washers.

“Diminished roller performance or incorrectly installed components can lead to very expensive repairs if not caught in time. In some cases, failure can lead to an unscheduled maintenance event. To overcome this, our rollers were designed as a single rolling element bearing that contains AeroTough, our self-lubricating polymer that does not rely on supplemental lubrication to maintain its function. As a result, an AeroTough King Air flap roller bearing will never seize.”

Flaps are a primary flight control surface on the aircraft with the rollers playing an essential part in their operation. Without these rollers, pilots don’t have that ability to extend and retract the flaps and operate the aircraft safely. The easy-to-install upgrade features a self-lubricating flanged polymer roller bearing with an integral thrust washer.

The AeroTough GF material eliminates the need to grease the flaps or use separate phenolic, steel or Teflon thrust washers, which are often misplaced or forgotten. It is also substantially tougher, but lighter, than any existing roller bearing solutions in the marketplace.

Marsh Brothers Aviation is confident that its bearing products, made from the advanced polymers developed by Burlington-based sister company Thordon Bearings for maritime, hydro power, pump and industrial applications, will benefit both the King Air and the wider aviation marketplace.

“We’re already seeing interest from operators in North America and Europe, where the King Air platform is widely used by fleet operators, air ambulances, military and defence government agencies,” said Choo-Son.

“For these types of operations, dispatch reliability is very important. If the flaps fail, that aircraft can be out of service for weeks getting the repair done, depending on the type of damage. Our grease-free polymers reduce that risk, and the costs associated with an unscheduled maintenance event. There is no supplemental lubrication to dry up, leading to degradation of the roller operation.”

The ability of the new flap roller system to resolve specific issues for aircraft users fits with Marsh Brothers Aviation’s vision to increase and revolutionize the use of self-lubricating polymer bearing and sealing technology across the aviation industry.

“We’re following through on one of our core philosophies, which is to identify a problem that is impacting the operators and the users of the aircraft, and to use our capabilities and material technology to provide a robust solution to that problem. This is just the beginning. Eventually, everything’s going to be made of grease-free, self-lubricating polymer materials in all aircraft,” he said.

The King Air Flap Roller kit is expected to receive Transport Canada and US Federal Aviation Authority certification and approval later this year.


A King Air flap roller with a AeroTough® GF thermoplastic polymer bearing (above left) from Marsh Brothers Aviation

About Marsh Brothers Aviation

Marsh Brothers, a Thomson-Gordon Group company, designs, engineers and manufactures proprietary self-lubricating and grease-free polymer technologies to improve the performance, reliability and service costs for aircraft owners, manufacturers and maintainers. Marsh Brothers’ polymers replace traditional metal bearings, seals and washers reducing component weight by over 80% in comparison. Less weight equals more fuel savings. Typical application includes landing gear pneumatic struts (bearings, dynamic seals and piston wipers), landing gear structures (link bushings), hydraulic actuators (seals, glands, piston rod wipers), flight controls (hinge bushings, rollers), passenger and cargo door hinge bushings and rollers.